Initially, computer systems were designed to support large organizations because the expense of early computers required that they address major organizational goals. These early computer systems included large mainframe minicomputer applications. However, the spread of personal computers created large markets for applications designed for individual users, such as spreadsheets and word processors. The cost of computation soon became inexpensive enough to be available to all members of some groups and a technological infrastructure, including networks and associated software, also became available. Both of these latter facts encouraged applications which supported communication and coordination between individual computers users. These interactive applications became more popular and, in the mid-1980s, the terms “groupware”, “collaborative computing”, “workgroup computing”, and “multi-user applications” were coined to describe such interactive or collaborative applications.
Conferencing applications, including desktop conferencing and videoconferencing, electronic mail, meeting support systems and group calendars are examples of groupware. However, early groupware systems suffered from the lack of integrated applications which allowed the different pieces of groupware system to operate together. Subsequently, several companies developed integrated groupware systems. One of the more popular of these integrated systems is the Notes™ groupware system developed and marketed by the Lotus Corporation, 55 Cambridge Parkway, Cambridge, Mass. “The Notes system is an information manager for workgroups which allows a group of people to share information across a computer network and combines e-mail, a shared calendar and shared databases in a client/server configuration. A Notes system consists of end-user workstation programs called “Notes clients” and one or more central server programs which provides services to the end users. Each server connects clients, routes mail, stores common information in one or more databases and determines how databases are shared among users. Users may also store in local workstation databases managed by the client software. The servers and the users are all connected together by a network. More recently, the Internet has arisen as a global, public information service which is becoming more and more popular. An extension of the basic Notes system called a Domino Web Server allows Notes databases to be accessed through a conventional web browser, such as Netscape Navigator™ or Microsoft Internet Explorer™. Users can then access Notes databases without installing Notes client software on every computer.
The Notes system also allows multiples copies, called “replicas,” of the same database to be kept on different servers or workstations. Replicas speed operation of the system by allowing users on a variety of network and at a variety of locations to access the same information. Replicas exchange information in a process called “replication” in order to make the information in each replica identical to the information in other replicas over time. For example, users in a first location can make changes to the information in a replica located in a server associated with the first location at the same time that other users make changes to information in a second replica of the same database located in a second server at another location. Later, during the replication process, when the first and second servers replicate, information will be exchanged among the replicas to make the information the same in both replicas.
In use, the Notes system can be configured for one or more “domains”, each of which is an organization of Notes servers that are centrally managed for server administration and security. All servers in a domain share a single database called a “public address book.” The public address book provides a directory of Notes servers, users, certifiers, domains, groups, connections and profiles. The public address book can also contain security information for each user that can include, for example, a digital “certificate” which is often a public key from a public/private key pair that is used with a conventional encryption/decryption algorithm to encrypt and decrypt e-mail message content.
The Notes system contains a number of features that make its use easier and more efficient. For example, a feature called “look ahead typing” allows a user to enter the beginning portion of a recipient's name in an e-mail address field and the Notes system will access the public address book to retrieve matching information to complete the name and provide the related information. Searching by recipient name is also provided. When a match is detected by the Notes system, additional information such as whether the mail should be encrypted, and, if so, the recipient's digital certificate can also be retrieved from the address book.
It is also possible for a user to use the Notes system with a remote or mobile computer, such as a laptop, that is not connected to a network or the Internet. In order to operate off-line, a user makes a replica of a database with the remote computer while the remote computer is connected to the Notes system via a network. The user then disconnects from the network and can operate in a normal manner. When the user later reconnects to the network, a replication operation is performed and the database in the remote computer is updated with the database replica in the Notes system.
In order for features such as the type-ahead and searching function to be available to a remote user, a copy of the public address book must also be placed on the remote computer. However, in large enterprises which may have many Notes domains, several different public address books may exist. If all of these are combined, to form one large address book the overall size would generally be too large for most remote computers, such as laptop computers. Therefore, the various public address books are compressed or abbreviated by means of a program called an “aggregator” which generates an abbreviated address book called a “directory catalog” which contains some of the information of the public address books, but is much smaller in size.
A problem arises when a remote user who is not connected to the Notes system attempts to use such a directory catalog to send an e-mail to a recipient listed in the catalog. The digital certificates which are used to encrypt e-mail are typically 1K–2K bytes in length, but may be up to 20K bytes in length. Because of this significant length, they are typically not included in the directory catalog. Therefore, if a user operating remotely and “off-line” attempts to send e-mail to a recipient where the e-mail must be encrypted, the digital certificate will not be available. Since information in the directory catalog records whether a user has a certificate or not, the e-mail routine will not allow the mail to be composed.
Therefore, there is a need to provide e-mail capabilities to an off-line groupware user who is operating with an abbreviated address book.